Improvement in balance slide-valves



F. STRATTNER.

Balance Slide-Valves.

Patented March IO. 18H.

.No.l48,523.

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/N//f/vfd/QJ cle/vidi Shawna UNITED STATES Errea FREDERICK STRATTNER, OF IVILMINGTON, DELAIVARE.

IMPROVEMENT IN BALANCE SLIDE-VALVES.

Specilication forming part of Letters Patent No. 14,523, dated March 10, 1874; application filed February 10, 1874.

To all whom it may concern Be it known that I, FREDERICK STuA'r'r- NER, of Vilmington, in the county ot New Casto which my invention appertains to make and use the same, I will now proceed to describe its construction and operation, referrin to the annexed drawing, in which- Figure l is a plan view, Fig. 2 a transverse vertical section, and Fis. 3 a longitudinal vertical section, ot' my valve and chest.

A represents the steam-chest with cover B. The slide-valve is made in two parts, C and D, the upper section G being' of proper size to seat itself against the inside cover or plate B', as shown in Figs. 2 and 3. The cover B, when screwed down tight against the chest, will spring up in the center, which would make it difficult to make a steam-tight joint; but the instant the steam strikes the upper section it forces it against the cover or plate B, when it does not matter whether the cover is sprung or not, as the joint is formed between the upper section C and the inside cover or plate B. The joint between the two sections ot the valve is broken by means ot' a band, E, of thin metal, which may be made in one or more pieces, according to the size of the valve. By the use of this band it requires no particular fitting, as the band will make a perfect joint on a casting taken out ot' the sand. rIhe band E is fastened on by rivets or screws, sufficiently far apart to make the band or apron free enough to allow air to pass between it and the valve when the engine is not using steam.

In alocomotive, when running down a grade, not using steam, the instant the steam is shut ott', there will be vacuum created in the steamchest, and by having the band or apron loose on the valve, the piston will draw air through the band. This band or apron being of thin or pliable met-al, the instant that the steam strikes it it is pressed against the valve and makes a solid valve of the two sections.

A V-shaped strip, a, with its ends overlapping the corners, may be used in large valves by iitti ng it in between the upper and lower sections ot' the valve, where they meet, by which device the space will be taken up as the valve wears 'at .the top and bottom by having the edges at the joint beveled. It will also prevent the band from setting in said bevels.

In place oi' the band, either one ot' the sections may be reduced at the joint to a featheredge and overlapping the other, it' so desired. In that case the corners mustbe cut to allow the steam to set them together, and these corners to be 1n ade perfectly steam-ti ght by means ot thin strips ot' metal riveted at one end and overlapping the cut corners, so that the steam will set them in and make themsteam-tight.

G represents the valve-stem, provided on its inner end with a T-head, b, and on the side ofthe valve are L-shaped iianges d, between which said head tits, so that the valve can easily be removed without raising the chest from its place. rlhe lower section D is provided with one or more air-valves, e, to supply the air that the cylinder may require, when not using steam, by drawing it through the cavity otA the valve. When the chest is filled with steam, the valve is'held down on the bottom ofthe chest on its seat by the pressure ofthe steam on the lid or projection P, but under the valve at each end is a spring, f, for the purpose of raising the valve off the seat the instant that the throttle is shut, thereby making it impossible for the piston to form a vacuum in the chest, as the air will pass in and out under the valve. In the lower section D ot the valve are studs L h, with springs i 'i bearing against the upper section C, for the purpose of keeping the same apart. The steamchest 'cover B has an inside movable plate, B', held by means of screws L k, and thus forming a double cover. valves m m, placed directly over the back or cavity of the valve, to supply air to the cylinder indirect-ly, it being conducted to the cylin rlhrough the cover are airder by the action ot' the valve. By this arrangement, the piston will draw pure air into the cylinderl when the engine is reversed or in back gear. XVhen it is necessary to :reverse the gearing to stop the engine, which is often the case, the instant that the gearing is reversed, the piston will draw air through the exhaust-pipes, thereby drawing cinders and ashes into the cylinders, and into the steamehcst and pipes, often cutting the valves. By placing the air-valves m m over the cavity of the slide-valves, they will be nearer to the valve than the exhaust-pipes, and they will, therefore, supply the air. u a are set-screws to force the parts B B of the cover apart, and straighten the lower part or plate B to make it a true face for the upper section C of the valve to work against. The space between the parts B and B is to contain air. This space may also contain steam by having a small hole through the plate B', in which case the set-screws are not necessary, as the steam will answer the saine purpose. G rep resents a connection for the oil-cup to be screwed on. This is screwed into the cover B, and provided with air-valves p j). In using` a seltoiler on steam-chests, the piston often draws the oil out of the cups when ruiming shut oft'. The valves p p open the instant the steam is shut olf, and when the piston should draw or form a vacuum it will be supplied through said air-valves, they bein g below the oil-cup, and will, therefore, stop the action on the lubricator.

rlhe balancing of the valves is accomplished by the upper section of the valve. By increasing the upper section the pressure is removed, and by decreasing the upper section the prcssure is increased on the lower section. As it depends on the displacement ot' the upper section altogether, it can be balanced to an exact point.

Having thus fully described lny invention, what I claim as new, and desire to secure by Letters Patent, is-

l. The band or apron E, in combination with the sections C I) of a balance slide-valve, arranged substantially asand for the purpose herein specified.

2. The springs f, arranged under the valves C D, for the purpose herein Specied.

3. The valves C D and ,inside cover or plate B', in combination withthe set-screws n a, constructed and arranged as and for the purpose herein described.

4L. rlhe valves G I), constructed with lip or projection I) and the springj", in combination with the inside cover or plate B and eoverB, when constructed and arranged substantially as and for the purpose herein set forth.

In testimony that I claim the foregoing as my own I aiiix my signature in presence ot' two witnesses.

FREDK. STRATTNElEt.

XViinesses:

HARRY GHRIsrY, DAvID It. HAYES. 

